How to get values from bpy.context inside a class
After a long while I finally understand it:
It's not possible to get the context inside a Class outside a function, (except of batFINGER's way, but I still don't understand that).
But it is possible to get what ever is needed in a function outside the class and then use the function like this: (Here is only the relevant part of the script shown)
-----&gt; In this way, the context won't update. Therefore the way over the &quot;@classmethod def poll(cls,context) is needed. (not shown here)
import bpy

def Multiview():
    if bpy.context.scene.render.use_multiview == True:
        print('Yes, its true')
        return True
    else:
        return False

class AddPresetObjectDisplay(AddPresetBase, Operator):
    '''Add a Object Display Preset'''
    bl_idname = &quot;camera.object_display_preset_add&quot;
    bl_label = &quot;Add Object Display Preset&quot;
    preset_menu = &quot;OBJECT_MT_display_presets&quot;

    # variable used for all preset values
    preset_defines = [
        &quot;obj = bpy.context.object&quot;
        &quot;data = bpy.context.data&quot;

    ]

    # properties to store in the preset
    preset_values = [
        &quot;obj.display_type&quot;,
        &quot;obj.show_bounds&quot;,
        &quot;obj.display_bounds_type&quot;,]

    if Multiview():          ####&lt;------- Context used here
        preset_values.extend([

        &quot;obj.show_name&quot;,
        &quot;obj.show_axis&quot;,])

Or another useful example:
def Blender_2_93():
    if bpy.app.version &gt;= (2,93,0):
        return True
    else:
        return False

With that little function is it very easy to  make changes for different blender versions if a preset system is used or something else where the access to context, data or what ever is not usual.